Backpacks have been known for many years as a convenient means of carrying loads on the back of a person while leaving his hands free. Backpacks are most typically used by military personnel in the field and by mountaineers and hikers.
A modern backpack is typically equipped with adjustable shoulder supports and a waist belt, both attached to the main pouch, or to a frame associated therewith, so as to most efficiently and comfortably locate the backpack on the back of a user. It has been recognized, however, as being desirable to enable adjustment of the position of the shoulder supports relative to the waist belt so as to fit the backpack with maximum comfort onto the back of a person.
One type of backpack on the market employs adjustable length straps for attaching the shoulder supports to the main pouch frame. A further type of backpack on the market employs a generally vertical track to which the shoulder supports are attached, the position of the shoulder supports being determined by tightening of a screw so as to fix them in a selected position. A disadvantage of the systems employed by these two backpacks is that the distance between the shoulder supports and the waist belt cannot be adjusted while the backpack is located on a person's back.
A further backpack on the market employs a shoulder support adjustment system wherein the shoulder supports are attached via adjustable straps to a track mounted on an adjacent portion of the pouch. While this system permits a reduction in the distance between the shoulder supports and the waist belt while the backpack is being worn, the back pack must be removed from the back of the wearer in order to increase the shoulder support-waist belt distance. A further disadvantage of this backpack is that it is properly supported on the back only when the weight of the load being carried in the backpack is predominantly exerted in the direction of the hips, or down the back. If the wearer of the backpack bends over forwards, however, the backpack tends to slip off the back.